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Publication numberUS974769 A
Publication typeGrant
Publication dateNov 1, 1910
Filing dateJun 15, 1909
Priority dateJun 15, 1909
Publication numberUS 974769 A, US 974769A, US-A-974769, US974769 A, US974769A
InventorsEdward J Hoff
Original AssigneeEdward J Hoff
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Seat for chairs and the like.
US 974769 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)




Patented N0v.1,1910




l sul? G11-Arun nrrBTrrnfi-lrn LYPLKUATIGI FILED IUXB 15, 19W.

Patented Nov. 1, 1910.



SEAT FOR CHAIRS spammen or 'terrassement AND THE LIKE.

Patented Nov. 1, 1910.

' Application bled .Tune 15; 1999. Serial Re. 502,307. 'Y

To all whom it may concern:

Be it known that I, EDWARD J. HOFF, a' citizen of the United States, residing at Berkeley, Alameda county, California, have invented certain new and useful Improvements in Seats for Chairs and the Like; and I do hereby declare the following to be a full, clear.l and exact description of the invcntion, such as will enable others skilled in the art to which it appertains to make and use the same.

This inventlon relates to certain improvements xn seats for chairs or the like; and

`the objects and nature of the invention will be readily understood by those skilled in the art in the light ofthe following explanation of the accompanying drawin illustrating what I now consider my pre erred embodi- :nent from among other formations, arrangements and combinations within the spirit and scope'o my invention.

My invention consists in certain novel fetures in construction and in combinations and arrangements as m'ore fully and particularly described and pointed out hereinafter.

Referring to the accompanying drawings Figure 1 is a side elevation showing a device of my invention in depressed position, portions -of the chair frame being shown in section. Fig. 2, is a similar vlew showing the seat in normal elevated position. Fig. 3, is a top plan View, the seat proper being broken away, and portions only of the bottom cleats thereofbeing shown.

ig. 4, is a detail view of certain parts. My invention contemplates the provision of an etiicient (what might be termed) counterbalanced seat for chairs or thelike, that is, a vertically movable seat provided with controlling and actuating or lifting means *designed to assist lthe occupant of the chair 'in r1sing therefrom, and-to break the shock vor to cushion the eiiect of dropping into or sitting down in the chair.

.""JConsiderable muscular elfort is involved @Qin 'the operation of rising from a chair to the `standing position, and the resulting lstrain and effort are particularly injurious ,and wearing in the case of persons who are weaklscinlirm or crippled, or very stout, or

with nursing or 'other mothers holding in- :fantsva '-fff z #It is'the. particular object-of my invention to provide a vertically movable seat having improved couuterbalancing or lifting mechsprings auism designed to permit the seat to settle gradually down to lowered or sustaining position under the weivht of the occupant ofthe chair, and to assist the chair occupant 1n rising by carrring part of the load and to that extent relieving the ,muscles of the individual; the device being peculiarly advantageous for use in arm chairs inasmuch as the occupant can lift the body by his or her arms when assisted by the comiterbaiancing or seat lifting mechanism, and thereby relieving the legs and back.

In the particular example illustrated, 1, is the rigid usually 0pm or rectan lar horizontal flame or the chair usua ly termed the seat frame and rigid with the chair legs .or supports. The supporting frame-Work of my seat controlling and lifting mechanism is carried by and arranged within the chair frame 1, and comprises a pair of horizontal flat spaced supporting bars 2, set down in frame 1 and extending from front to rear y,

thereof and having upturued vertical ends 20, secured to the inner-edges of the front and rear cross bars of frame 1, by screws about as shown so that the frame bars 2, are depressed within frame 1. The horizontal supporting bars 2, carry encircling or rectangular horizontal open frame 3, set down in rame 1, and if so desired formed of a fiat strong band of metal set c-n edge and bent to forni the front and' rear and usually parallel sides of the frame, and fixed to and on bars 2, by corner brackets having horizontal feet bolted or otherwise secured on the bars 2. The two vertical front brackets 4, are extended upwardly to carry and form bearings for a shaft, while the two rear brackets 5,' are extended upwardly to enter and form guiding holders for upwardly projecting coiled expansive cushioning 6, is the vertically and angularly movable chair seat which in the present instance is showndiagrammatically, for in practice said seat can be of any suitable or desirable for mation, such as u bolstered, or plain, or of any suitable inis material, or body. I show this seat at lts under side provided with la pair of s aoed depending. flanges or' cleats 60, exten ing rearwardl from the front portion thereof, and usua l arranged in vertical planes parallel with t e vertical planes of the sides of frame 3, and directly over the cushion springs 50.

7, is a horizontal rock shaft arranged Al the outerside faces of the rear ends of the Q l i v 974,769 I transversely of the front end of the frame 3, and mounted to rock in the projected upper 'ends of the brackets 4.

A lifting frame is arranged between the seat 6, andl the frame 3, and is pivotally joined to the rear portion of .the seat and to the frame 3, through the medium of the rock shaft. In the specific example illustrated, this lifting frame consists of a pair of arallel links 8. at their rear ends arrange at cleats 60, being pivotally coupled thereto by the horizontal pin or shaft 80. The front` portions of the iinas 8, are iooseiy nini-inten to rock or oscillate on the end portions of' ,after set forth.

9, are sleeves arranged on and ied to the end portions of the rock shaft i to rock therewith. The sleeves are formed with Y reai'wardly'extending lateral or crank liftingzarms 92, arranged between the links -8 of the lifting frame and extending rear wardly beneath the stop bar 82 of the lifting frame, anu at their rear end s a distance in rear of the lifting bar 82, said arms 92 are connected to the seat 6 about midway between the front and rear ends thereof. This connection can be established through the medium of stiff comparatively s hort linksl93 at their u per ends pivotally oined to the cleats 60 y cross pinior sha t 94, and at their lower ends loosely or ivotally joined to the rear ends of the lifting arms 92, in any suitable manner or by any suitable means, as by pivot pins 95. V

Suitable connections are arranged between the strong contractile coiled lifting s n rings 91, and the lifting shaft 7, to constant y tend to roel-i the shaft in a direction to raise the seat. Various connections can be employed for this urpose. For instance, merely as Aan examp e, I show depending quadrants 90,

rigid with the sleeves 9, and flexible pull connections, such as chains 96, at their rear ends secured to the front ends of said springs, and at their front portions secured to the` uadrants, to operate in a manner well un erstood by skilledr mechanics.

A brace is provided between the rear bar ofxthe frame 3,v and the central or intermediate portion of the rock shaft 7, and in the particular example illustrated, this brace consists of a longitudinally threaded rod 10,

assing loosely t rough the reargend ofthe rame 3, and secured thereto in lon tudinal adjustment by the nuts 11. At its A ont end this rod is ri id with the central portion of a,

yoke, Y or ork 12, at its front ends having open bearings 13 held pressing forwardly against the rock shaft 7 to brace said shaft against buckling or bending under the heavy strain to which it is subjected. Wear can be taken up by the iiuts 11 to maintain the parts under the tension desired.

The rear ends of the two heavy strong contractile springs 91 are coupled to and are joined by the head or evener bar 97 adjustable longitudinally of and through which the screw or rod 1U, loosely extends. This evener 97 bears forwardly against and is held in the desired adjustment by a large wheel or 98, arranged on and ine-sliiiig with the threads of the rod 10, and longitudinally adjustable thereof to vary Qthe tension of the springs 91 and the lifting pull or power thereof on the lifting ineclianism.

The springs 91, constantly tend, through the medium of the chains 96, arms 90,and the 'rock shaft., to elevate the arms 92 and these arms engage the stop bar 82 of the lifting frame 8 and tend to elevate said .frame and th rear end of the seat until the ends 81 of said frame engage frame 3 and thereb limit further upward movement of the li ting frame. The links 93, applied to the seat advance of the pivotal conuection 80, between the lifting frame and the rear Aend of the seat, lift the front end oi" `the-seat forwardly and from the intermediate portions of the lifting frame 8, so that in its normal position the seat elevated s.

considerable distance from the chair frame 1 and is also projected forwardly therefrom and is inclined downwardly and forwardly from its rear end. The lower front edge of the seat will engage a person about to cccupy a seat just above the knees and the initial movements ofthe body in settling into the seat will tend to swing the seat rearwardl tension o` sprin s 91 and when the whole weight of the bo y is thrown on the seat the springs will resist sudden depression of the lifting mechanism, causing the saine to settle gradually and without shock upon the cushioning springs 50 and until the links 93 force the arms 92 downwardly from the si op bar 82 permitting the cleats (3C te drop onto said cross bar 82 and the seat to assume its final lowered body supporting position. When the ocou ant starts to rise from the chair, usuall the front en of the seat will rise until the arms 92 engage the stop bar S2 and frame S will thereupon swing upwardly to elevate the seat from its rear end carrying a portion of the weight of the'occupant and materially assisting the operation of rising from the chair.

It should be understood that the springs can be easily adjusted to attain the desired and downwardly against the v y assisting with the arnisj-z 30 nections between the rear ends of said arms 50 ing frame, a normally elevated seat having a .974369 l j a intention that the springs should be adjusted to snit tbe particular weight of the person usually occipying the chair or for whom the chair is' esigned. y v ,5 In the particular example illustrated, I

have shown my seat lifting or connterbalancing device constructed so as to be apolicable to various constructions of chairs, that is so that the device can be made and sold for 'application to chairs by manufacturers of chairs, or by dealers or artisans to chairs in the beine, but I do not so wish to limit my invention..

It is evident that various changes and modifications mi ht be resorted to without departing from t e spirit and scope of my invention, and hence I do not wish to limit yself to the particular' construction illustrated.' What I claim is v 1. In combination, a supporting `traine, a vertically 'movable seat, a frame at its front end pivctally joined to the front portion of Y said frame and at its rear end pivotally joined to the rear portion of said seat, vertically movable angle levers carried by said frame and having upwardly and rearwardly extending lifting arms to engage said pivotally joined frame to lift the seat, link conand said seat in advance'of its rear end, and a seat counterbalancing and lifting spring device carried by said frame and coupled to s aid angle levers to swing tbe same to lift the seat.

, 2. In a chair, in combination, a vertically movable seat, a supporting frame, a swinging lifting frame ulerumed to the supporting frame below the front end of the seat .40 and extended rearwardly and joined to the rear end o'f the seat to lit the rear end of the seat and project its front end forwardly, a vertically movable lifting-'trame-elevating member having an independent lifting connection to the seat to elevate its roiit end, vand an actuating spring device comprising a retraetive spring and pull connections .to said member.

3. In a chair, in combination, a supportmounted at its rear end to swing on a vertically movable transverse axis, sup orting means applied to the rear end of t e seat and mova le in an upwardly and forwardly curving arc to project the seat forwardly and elevate its rear end, a vertically movable actuating member for said means, a seat-swinging connection from said member to said seat for swinging the same on said axis to elevate its forwardly projecting front end, and an actuating retractive spring deiece having a pull connection to said mem- 4. In combination, a supportin frame, a Si vertically and forwardly movalile seat, a vertically swinging frame at its rear end pivotally joined to the rear of said seat and at its front pivotally joined to the front portion of said supporting frame and provided 'it with a stop to limit the upward and forward movement of said seat, a vertically movable lifting arm ulcrumed to said supporting frame and having link connections with said seat ir. advance of its rear end for elevatinv 7| the front end of the seat, said arm adapted `to engage said swinging frame to elevate the rear end of the wat and to project the seat forwardly, and a spring device provided with a pull connection to said 8: arm for actuating the same.

5. In combination, a supporting frame, a vertically movable seat, a swinging frame pivotally joined to the supportingv frame and to the seat for lifting the same and com- 8 prising an intermediate Across bar, a vertically movable lifting arm fnlcrumed to the supportingframe and arranged beneath and toengage said cross bar and thereby elevate said swinging frame to raise the rear end of 9 the seat, a connection from said lifting arm to the seat to elevate the front end of the seat, and a retractive spring device for elevatin` said seat provided with an operative pu connection to said arm.` f Y 9 In testimony whereof I affix my signature, in presence of two witnesses.


Witnesses F. M. Ronniivo,

vertically movable free front end and E. F. Gnn'rrrn.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3218102 *Mar 27, 1963Nov 16, 1965Specketer Francis La MonteInvalid chair
US3250569 *May 25, 1964May 10, 1966Edward J GaffneyElevator seats
US3623767 *Aug 22, 1969Nov 30, 1971Invalift IncInvalid lifting seat
US4833736 *Nov 17, 1987May 30, 1989Sadler Edward DSeating assist apparatus
US4852849 *Feb 17, 1988Aug 1, 1989Jones Eifion RLifting seats
US4993777 *Oct 18, 1989Feb 19, 1991La-Z-Boy Chair CompanyRecliner chair lift base assembly
US5011224 *Nov 20, 1989Apr 30, 1991Paul Gerald SArise-assist chair
US5314238 *Sep 28, 1992May 24, 1994La-Z-Boy Chair CompanyCam guide drive mechanism for power-assisted chairs
US5466046 *Nov 19, 1993Nov 14, 1995La-Z-Boy Chair Co.Linear actuation drive mechanism for power-assisted chairs
US5482350 *May 6, 1994Jan 9, 1996La-Z-Boy Chair CompanyLinear actuation drive mechanism for power-assisted chairs
US5513867 *Aug 24, 1993May 7, 1996University Of UtahSeat-lift wheelchair
US5601338 *Mar 23, 1995Feb 11, 1997Michigan Seat CompanySeat structure with adjustable suspension
US5651580 *Jun 7, 1995Jul 29, 1997La-Z-Boy Chair CompanyLinear actuation drive mechanism for power-assisted chairs and base therefor
US5794911 *Feb 5, 1996Aug 18, 1998Milsco Manufacturing CompanyAdjustable vehicle seat suspension
US5876085 *Feb 27, 1997Mar 2, 1999Milsco Manufacturing CompanyAdjustable vehicle seat
US5927679 *Apr 21, 1997Jul 27, 1999Milsco Manufacturing CompanyAdjustable vehicle seat suspension
US6186467May 6, 1999Feb 13, 2001Michigan Seat CompanyFull seat adjustable suspension
US7000988Aug 12, 2003Feb 21, 2006Universal Product Development Company, LlcLift chair
US7874620Jan 25, 2011Herman Miller, Inc.Health care chair
US20050046255 *Aug 12, 2003Mar 3, 2005Bressler Peter W.Lift chair
US20090188028 *Jul 30, 2009Jin Shan JiangAuxiliary descending device for a toilet seat
US20090250979 *Apr 4, 2008Oct 8, 2009Kooistra Brett WHealth care chair
EP0787621A2Feb 4, 1997Aug 6, 1997Milsco Manufacturing CompanyAdjustable vehicle seat suspension
WO2015040008A1 *Sep 16, 2014Mar 26, 2015Martin BliemItem of seating furniture
Cooperative ClassificationY10S297/10, B60N2/502